The present invention relates to a system and method for automatically cleaning a single roll or batch processor by using ultrasonic energy.
Photoprocessing equipment sold in the trade requires regular (daily, weekly and monthly) cleaning to maintain the quality of images. Continuous transport processors for silver halide based sensitized media typically include a series of tanks holding various solutions (e.g. developer, acid stop bath, bleach accelerator, bleach (oxidant), fix (silver removal), stabilizer, final rinses and water rinses) employed not necessarily in this order or combination. The sensitized media is transported through these solutions through a system of roller assemblies. With daily use, the tanks (although they may be replenished to remove some soils and maintain activity levels) develop soils. In the traditional consumer negative processes the soils (by-products) generated in each processing step are identifiable for someone knowledgeable in the field, and they are in general confined in the tank (step where they are produced) or in the subsequent step (as carried-over by the sensitized media). Some of the soils that are of interest to the photographic industry are listed here: developer tar (e.g. para-phenylenediamine polymerization and/or oxidation by-products), various salts (e.g. thiosulfate, chelated iron), various calcium, magnesium, and aluminum salts, silver salts of varying solubility, by-products of reactions happening in the sensitized media, or a result of the quality of the local water source and so on.
Other sources of soil in photographic processors include the following: fragments of gelatin or other hydrophilic colloids that may be removed from the photographic material during processing, fragments of overcoat layers, matte layers, anti-static layers, or magnetic recording layers that may be removed from the photographic material during processing, fragments of photographic material (for example skivings that remain after the cutting, slitting, chopping, or perforating of the photographic material during its manufacturing) that are released into the processor or processing solutions, and deposits of biogrowth that may contaminate processing solutions or processor surfaces that come in contact with processing solutions, including stabilizers, rinses, and washes. Regular cleaning is used to avoid quality or yield losses because of chemical contamination or physical damage to the sensitized media.
This problem is exacerbated in single roll or single use (batch) processors. These machines may encounter lower productivity (infrequent use). In this type of equipment small amounts of chemicals are used to process the sensitized media in a single container. The process may include a color forming step, as well as steps for silver removal and rinsing of the media that were described above, and even combinations/consolidations of steps. This type of equipment is desirable for its increased flexibility (can accommodate several of the standard silver halide process cycles e.g. C-41, E-6 etc. depending on the chemical supply provided), but that same flexibility increases the risk for cross-contamination when small amounts of fluid form deposits in the container. It may also lead to catastrophic failure during loading and/or unloading of the next roll of sensitized media on the soiled sticky surfaces.
The present invention provides for a photographic processor which includes an automated cleaning arrangement or member that cleans the components of the photographic processor in an efficient manner. That is, the present invention provides for a system and method that provides an automated cleaning cycle in a photographic processor, and more specifically, photographic processors in the form of batch (single roll) processors. The system and method of the present invention overcomes common soil problems in batch processors that results in image quality loss (contamination) or catastrophic failure (tear during loading of sensitized media).
The cleaning arrangement of the present invention includes a transducer and ultrasonic probe assembly that is integrated into the processor and generates ultrasonic energy in cleaning solution as necessary. The probe can be stationary or mobile. The cleaning cycle or stage of the photographic processor of the present invention can be activated on demand or in planned intervals and does not require operator time or operator handling of any chemicals. The cleaning arrangement of the present invention can further use recycled or replenished cleaning solution for higher efficiency. In the system and method of the present invention, the solution can be delivered at room temperature or can be preheated.
The cleaning arrangement of the present invention can also utilize a liquid level sensor to confirm the presence of adequate cleaning fluid in the photographic processor before the ultrasonic source is activated to avoid damaging a probe of the cleaning arrangement.
The present invention accordingly provides for a photographic processor that comprises a circular processing drum having a processing chamber therein for processing photographic film; a disk positioned inside the drum and having one or more sets of disk teeth along an outer perimeter of the disk, with the disk teeth being capable of interengaging with holes along an edge of photographic film to be processed to transport the photographic film along a film path in the processing drum; and a cleaning arrangement comprising a transducer and a probe, with the transducer and the probe being adapted to provide ultrasonic energy to a cleaning solution provided in the processing chamber during a cleaning stage of the photographic processor to clean components of the photographic processor.
The present invention also provides for a photographic processing apparatus for processing photographic material which comprises a processing chamber for processing photographic media; and a cleaning arrangement which comprises a transducer and a probe, with the transducer and the probe being adapted to impart ultrasonic energy to cleaning solution provided in the processing chamber during a cleaning stage of the photographic processing apparatus.
The present invention also provides for a method of operating a photographic processor to process photographic media which comprises the steps of inserting photographic media into a processing drum; supplying and discarding processing solution into and from the processing drum during a processing stage to process the photographic media; supplying a cleaning solution to the processing drum during a cleaning stage; contacting the cleaning solution with an ultrasonic probe; and selectively activating the ultrasonic probe in contact with the cleaning solution to impart ultrasonic energy to the cleaning solution and clean components of the photographic processor.
The present invention further provides for a method of cleaning a processing chamber of a photographic processor which comprises the steps of supplying a cleaning solution in the processing chamber; contacting the cleaning solution with an ultrasonic probe; and selectively activating the ultrasonic probe in contact with the cleaning solution to impart an ultrasonic energy to the cleaning solution and clean components of the photographic processor.